Daniel Lee Lopez, who had petitioned the courts to speed up his execution date after being convicted of killing a Texas cop, was put to death on Wednesday in Huntsville against the efforts of his attorney.

A Texas Department of Criminal Justice spokesman said Lopez died of lethal injection at 6:31 p.m., according to the Huffington Post. He was convicted of killing Corpus Christi Police Lt. Stuart Alexander during a high speed chase there in 2009.

The Corpus Christi Caller-Times said Lopez struck Alexander with his sports utility vehicle while fleeing from police. Lopez claimed he hit Alexander accidentally because he had been pepper sprayed.

He was convicted and sentenced to death in 2010. Lopez asked for a swift execution, and said in a letter to the Caller-Times that he wanted his six children to be able to move on.

"How do you start a letter knowing this will be the last one?" he wrote. "The last two (children) is what hurts me the most because they know I'm their dad and they tell me they love and miss me. They ask when I'm coming out to be with them."

In 2013, Lopez filed a handwritten motion to a state district court telling a judge that he wanted to be executed, according to KIII-TV. He included a psychological evaluation that showed he was competent and understood what he was doing, noted the television station then.

Lopez's attorney, David Dow, though, continued to fight to keep his client from being executed, said the Huffington Post. The execution moved forward only after Dow's last appeal to the U.S. Supreme Court was denied.

Dow, an anti-death penalty defense attorney, told the court that Lopez suffered from "obvious and severe mental illness," which was demonstrated by his "well-documented history of irrational behavior and suicidal tendencies."

Dow argued that Lopez didn't intend to kill Alexander, making him ineligible for the death penalty.
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Daniel Lee Lopez, who had petitioned the courts to speed up his execution date after being convicted of killing a Texas cop, was put to death on Wednesday in Huntsville against the efforts of his attorney.